Project Summary/Abstract Over 5 million Americans provide informal Alzheimer's Disease (AD) caregiving, which negatively impacts caregivers' health and is associated with a 63% greater risk of mortality as compared to non-caregiving controls. Insomnia occurs in over 60% of AD caregivers and has independent negative influences on caregiver health and mechanisms of disease risk. Although insomnia is a modifiable risk factor, no prior study has targeted insomnia in AD caregivers. The ongoing randomized control trial, CARES, is evaluating the non-inferiority of Mindful Awareness Practices for Insomnia (MAP-I ) vs. Cognitive Behavioral Therapy for Insomnia (CBT-I) on outcomes of insomnia, cellular and genomic markers of inflammation, and cellular aging in older adult AD spousal caregivers with insomnia (N=150) over one-year follow-up. This supplement project will measure and estimate the costs associated with implementing the MAP-I and CBT-I interventions in the CARES trial. A micro-costing method will be used to itemize and abstract costs of all components included in each of the two interventions to estimate total and per-participant costs per intervention. For each step in each intervention arm, all inputs ? including personnel, patient time, supplies and equipment ? will be inventoried and measured. Unit costs will be applied to the quantities of each such resource consumed, and results will be summed to obtain total costs per component and overall for each of the MAP-I and CBT-I interventions. Per-participant costs will be estimated by dividing total costs by number of participants. The analysis will end with sensitivity analyses to evaluate the robustness of estimates to changes in key cost components.